The early humans that left these prints were bipedal and had big toes in line with the rest of their foot. This means that these early human feet were more human-like than ape-like, as apes have highly divergent big toes that help them climb and grasp materials like a thumb does. The footprints also show that the gait of these early humans was "heel-strike" (the heel of the foot hits first) followed by "toe-off" (the toes push off at the end of the stride)—the way modern humans walk.

The close spacing of the footprints are evidence that the people who left them had a short stride, and therefore probably had short legs. It is not until much later that early humans evolved longer legs, enabling them to walk farther, faster, and cover more territory each day.

Two dating techniques were used to arrive at the approximate age of the beds that make up the ground layers at Laetoli: potassium-argon dating and stratigraphy. Based on these dating methods, the layers have been named and arranged in the following order (from deepest from the surface to closest to the surface): Lower Laetolil Beds, Upper Laetolil Beds, Lower Ndolanya Beds, Upper Ndolanya Beds, Ogol lavas, Naibadad Beds, Olpiro Beds, and Ngaloba Beds. The upper unit of the Laetolil Beds dated back 3.6 to 3.8 million years ago. The beds are dominantly tuffs and have a maximum thickness of 130 meters. No mammalian fauna were found in the lower unit of the Laetolil Beds, and no date could be assigned to this layer.

The Ndolanya Beds, which are located above the Laetolil Beds and underlie the Ogol lavas, are clearly divisible into upper and lower units separated by a widespread deposit of calcrete up to one meter thick. However, like the Lower Laetolil Beds, no date can be assigned to the Ndolanya Beds. The Ogol lavas date back 2.4 million years. No fauna or artifacts are known from the Naibadad Beds, and they are correlated with a bed layer at Olduvai Gorge based on mineral content. Pleistocene fauna and Acheulean artifacts have been found in the Olpiro Beds. Based on a trachytic tuff which occurs within the beds, the Ngaloba Beds may therefore be dated between 120,000 to 150,000 years BP.

Resuming this top to bottom, as one digs down (qualification on this description, see below):

1) Ngaloba Beds,

"Based on a trachytic tuff which occurs within the beds," i e presumably Ngaloba, not Olpiro, "the Ngaloba Beds may therefore be dated between 120,000 to 150,000 years BP."

2) Olpiro Beds,

where Pleistocene fauna and Acheulean artifacts have been found. (Stratigraphy used)

3) Naibadad Beds,

No fauna or artifacts are known. Same mineral content as a bed layer at Olduvai Gorge.

4) Ogol lavas,

date back 2.4 million years (presumably potassium-argon = worthless).

5) Upper Ndolanya Beds,

No date.

6) Separation

a widespread deposit of calcrete up to one meter thick.

7) Lower Ndolanya Beds,

No date.

8) Upper Laetolil Beds,

The stratum of the footprints? Not directly said in wiki, but definitely in the other link "3.6 million years old". (stratigraphy)

9) Lower Laetolil Beds,

No date. "No mammalian fauna were found in the lower unit of the Laetolil Beds, and no date could be assigned to this layer."

Again, same levels, but now only with results/method or lack of result:

I might retort, if palaeos find dates on samples that are older on higher layers than on lower, what do you think they do? They discard the aberrant dates (aberrant according to their theory there must have been much time between them), publish the acceptable ones. In a fine printed footnote they might acknowledge aberrant dates, if they hint at an acceptable (or even unknown) explanation for them. That is the way that community works. At least that is how Kent Hovind characterises them, and I have seen him challenged for making up references and then I have found he hasn't.

So, stratigraphy is not worthless perhaps if potassium-argon is ... what are the biostratigraphic units? Olpiro beds (level 2 from top) above Upper Laetoli beds (level 8 from top).

In Upper Laetoli beds you find footprints which could easily have come from a modern human, as Kent Hovind observed in a video, but must "in fact" have come from "a human ancestor" since found under a layer (worthlessly) dated 2.4 million years before present, i e before humans anatomically our own species are supposed to have developed.

If not found that way, the short legs would have been explained by one individual being a dwarf or a child.

I would date the Pliocene layer to the Flood of Noah. I would date the Pleistocene layer to post-Flood centuries of stone age technology. Not because Pleistocene is automatically younger than Pliocene, but because it is a higher and later biostratigraphical layer found in the same locality.

I am of course presuming the footprints of Upper Laetoli beds and the Acheulean axes from Olpiro beds and the seven non-bio-stratigraphic layers are all same locality, different depth. Otherwise, there is no reason why Olpiro beds couldnt also be from flood in a locality a bit beside the foot prints.